Seroprevalence and Risk Factors of Crimean-Congo Hemorrhagic Fever in Cattle of Smallholder Farmers in Central Malawi

Crimean-Congo hemorrhagic fever virus (CCHFV) is endemic in Africa, Asia, and Eastern Europe where it circulates among animals and ticks causing sporadic outbreaks in humans. Although CCHF is endemic in sub-Saharan Africa, epidemiological information is lacking in many countries, including Malawi. To assess the risk of CCHF in Malawi, we conducted an epidemiological study in cattle reared by smallholder livestock farmers in central Malawi. A cross-sectional study was conducted in April 2020 involving seven districts, four from Kasungu and three from Lilongwe Agriculture Development Divisions. A structured questionnaire was administered to farmers to obtain demographic, animal management, and ecological risk factors data. Sera were collected from randomly selected cattle and screened for CCHF virus (CCHFV) specific antibodies using a commercial ELISA kit. Ticks were collected from cattle and classified morphologically to species level. An overall CCHFV seropositivity rate of 46.9% (n = 416; 95% CI: 42.0–51.8%) was observed. The seropositivity was significantly associated with the age of cattle (p < 0.001), sex (p < 0.001), presence of ticks in herds (p = 0.01), district (p = 0.025), and type of grazing lands (p = 0.013). Five species of ticks were identified, including Hyalomma truncatum, a known vector of CCHFV. Ticks of the species Hyalomma truncatum were not detected in two districts with the highest seroprevalence for CCHF and vector competency must be further explored in the study area. To our knowledge, this is the first report of serologic evidence of the presence of CCHV among smallholder cattle in central Malawi. This study emphasizes the need for continued monitoring of CCHFV infection among livestock, ticks, and humans for the development of data-based risk mitigation strategies.

A preliminary study on the Monthly dynamics of cattle tick infestation in Sokoto, north western Nigeria

The distribution and monthly dynamics of bovine ixodids in Sokoto Township and environs were recorded between Jan 2009 and Dec 2010. Monthly tick collections were performed on 400 animals from which a total of 12, 296 ticks were collected. Ticks from each cattle were collected separately using a pair of blunt forceps, into labelled universal bottles containing 70% ethanol into which 5% glycerine was added to keep specimens better preserved. On each label, the location, breed of the animal, number of ticks and date of collection were recorded. In the laboratory, Ticks were placed into petri dishes, counted, examined and identified with the aid of a dissecting stereoscope based on morphological Characteristics and aided by the use of standard keys according to Hoogstraal (1956) and Walker et al. (2003). These include Hyalomma truncatum (15.5%), Hyalomma dromedarii (13.3%), Boophilus decolaratus (11.3%) Amblyomma variegatum (10.6%), Hy. impeltatum, (10.1%), Hy. rufipes (9.4%), Hy. impressum (7.4%), Boophilus annulatus (4.4%), B. geigyi (4.3%), Rhipicephalus sanguineus (4.1%) Amblyomma hebraeum (3.4%), Rh. evertsi (2.6%), A. pomposum (2.0%), Rh. lunulatus (1%) and Rh. senegalensis (0.5%). Hyalomma. truncatum, Hy. impeltatum, Hy. Impress B. annulatus, A. hebraeum, A. pomposum, Rh. lunulatus and Rh. senegalensis were recorded for the first time in the Study area. The distribution and dynamics of cattle ixodid ticks has not been hitherto chronicled in the study area.

Ticks (Acari: Ixodidae) infesting cattle and African buffaloes in the Tsavo conservation area, Kenya

Several ixodid tick species are shared between domestic cattle and African buffaloes (Syncerus caffer). So too, are a number of tick-borne diseases. The aim of the study was to compare the species composition of ticks that infest cattle and buffaloes utilising the same habitat within the Tsavo Conservation Area, Kenya. To this end, 25 cattle and 62 buffaloes were each opportunistically sampled for ticks on a single occasion in February 2010. Eight species, namely Amblyomma gemma, Amblyomma lepidum, Hyalomma albiparmatum, Hyalomma rufipes, Hyalomma truncatum, Rhipicephalus evertsi evertsi, Rhipicephalus pravus and Rhipicephalus pulchellus infested both cattle and buffaloes. Three species, Rhipicephalus (Boophilus) sp., Rhipicephalus kochi, and Rhipicephalus muehlensi were collected only from cattle, and three species, Hyalomma impeltatum, Rhipicephalus humeralis and Rhipicephalus praetextatus were present only on buffaloes. The attachment sites of the various tick species were also recorded. New locality records for H. impeltatum and H. truncatum and the first confirmed locality record for Rhipicephalus praetextatus sensu stricto in Kenya were documented.

Ticks (Acari: Ixodidae) infesting camels (Camelus dromedarius) in Northern Sudan

Monthly total body tick collections from 13-20 camels were conducted for 2 consecutive years (2000-2001) in Northern Sudan. Tick populations were correlated with locality, season, predeliction site, sex and coat colour. Hyalomma dromedarii was found to be the predominant (89 %) tick species infesting the camels. Other tick species found in very low numbers were Hyalomma impeltatum (7.7 %), Hy alomma anatolicum anatolicum (3.3 %), Hyalomma truncatum (0.29 %), Hyalomma marginatum rufipes (0.25 %), Rhipicephalus praetextatus (0.30 %) and Rhipicephalus sanguineus group (0.09 %). Nymphs of the genus Hyalomma were collected in significant numbers. Adult ticks significantly preferred to attach to the lower parts of the camel's body for feeding while the nymphs preferred the back of the animal.